title: Investigations on radiosensitive and radioresistant populations of Drosophila melanogaster. XII. The resistance factor rar-3: stage specificity.
abstract: In earlier studies the recessive genetic factor rar-3 (3-49.8) of Drosophila melanogaster had been found to reduce the sensitivity of immature oocytes to the mutagenic action of X-rays. The present work was devoted to an extension of these studies to other germ-cell stages in both male and female and also somatic cells. The results show that, in the female, the effects of rar-3 are manifest in all germ-cell stages including gonia and nurse cells but not in mature oocytes. In the male germ-cell stages, rar-3 was without any measurable effect; maternal-effect studies were likewise negative. Somatic tissues were also unaffected. Furthermore, rar-3 was apparently not active in larval oogonia. It is therefore concluded that the activity of rar-3 is switched on in oogonia during puparium formation or metamorphosis and persists until before the formation of the mature oocyte.
mesh_terms: D000818:Animals; D004331:Drosophila melanogaster / Q000235:genetics*; D005260:Female; D005796:Genes; D007814:Larva / Q000528:radiation effects; D008297:Male; D008540:Meiosis; D009865:Oocytes / Q000528:radiation effects; D010641:Phenotype; D011836:Radiation Tolerance; D013094:Spermatozoa / Q000528:radiation effects; D014965:X-Rays